The sure sign that Brian O'Neill has been there is if you open it up and see epoxied rivets. Frankly, I think that's more cosmetic than anything but ya never know. I won't be dropping one from a ladder so assume the best.
Funny, I just had it open examining that.
Depending on the type of adhesive...assuming something decent...it might actually be structurally significant.
However, the dabs over existing rivet heads are going to be 100% cosmetic; all it does is prevent you realizing when those rivets break.
This probably complicates an eventual bolt mod, but if it does what it might do, then a bolt mod may not be truly necessary for a long time either way.